Question: Khan.scratchpad.disable(); William sells magazine subscriptions and earns $$8$ for every new subscriber he signs up. William also earns a $$25$ weekly bonus regardless of how many magazine subscriptions he sells. If William wants to earn at least $$71$ this week, what is the minimum number of subscriptions he needs to sell?
Answer: To solve this, let's set up an expression to show how much money William will make. Amount earned this week $=$ $ $ Subscriptions sold $\times$ Price per subscription $+$ Weekly bonus Since William wants to make at least $$71$ this week, we can turn this into an inequality. Amount earned this week $\geq $71$ Subscriptions sold $\times$ Price per subscription $+$ Weekly bonus $\geq $71$ We are solving for the number of subscriptions sold, so let subscriptions sold be represented by the variable $x$ We can now plug in: $x \cdot $8 + $25 \geq $71$ $ x \cdot $8 \geq $71 - $25 $ $ x \cdot $8 \geq $46 $ $x \geq \dfrac{46}{8} \approx 5.75$ Since William cannot sell parts of subscriptions, we round $5.75$ up to $6$ William must sell at least 6 subscriptions this week.